Selection of properly sized eyeglasses is one of the most difficult problems in fitting eyeglasses to a wearer. The current method for selecting eyeglass frames is a subjective approach wherein the selection is based primarily on cosmetic considerations rather than proper physical fit. Even when physical fit is considered in the selection of frames, the criteria is subjective and depends very much upon the skill of the fitter. The typical criteria for judging physical fit relies on such subjective considerations as face shape, length of face and facial balance. Until the invention of the present method, there has been no objective way to ensure the proper physical fit of frames
The difficulty in fitting frames is exacerbated by the large number of different frames which are available. The wearer is typically unskilled in judging which frames being offered for sale are the correct size for his or her head, and consequentially is unable to limit his or her search to those frames which are the proper physical size. Without such a limitation on the wearer's search, the wearer will typically select frames based only on cosmetic considerations and frequently selects frames which appear aesthetically pleasing as displayed but which are not the proper size for the wearer's head. Once the wearer has made such a selection of improperly sized frames, it is typically awkward and difficult for the fitter to persuade the wearer that the selected frames are not the right size. An objective system approach is more likely to be accepted by the wearer, than statements about size made only by the fitter.
There are different systems for identifying various measurements of frames. One such well known system widely used is the "boxing system", in which rectangular boxes are modeled about each lens opening of the frame. The horizontal measure of this box is referred to as the eye size, and is denoted by the letter "A". The distance between each box is known as the distance between lenses or bridge size, and designated by the letters DBL.
Manufacturers of frames which are sized according to the boxing system typically mark the frame using the format: A.quadrature.DBL. For example, such a marking might appear as: 52.quadrature.22, meaning that the eye size of the frame is 52 mm and the distance between the lenses is 22 mm. Generally, the eye size measurement for different sizes of frames of a given style change in two millimeter increments, such as 50 mm, 52 mm, 54 mm, etc.
Although the boxing system provides an objective standard for sizing the lens opening and bridge size, it does not provide any indication of the overall width of the frame, because there is an overhanging portion on either side of the frame extending beyond the outer edge of the boxing system. The boxing system does not indicate the spacing between the temples of the frames which is important to the selection of properly fitting frames. The boxing system also does not provide a way to distinguish between frame sizes. For example, the distance between the outer lens edges for a 54.quadrature.16 is the same as for a 52.quadrature.20. The boxing system does not provide a way to group the frames according to their temple to temple widths.
Thus, there is a need for a method of fitting frames which is based on objective criteria and which is easily understood.